JMortensen

I think you'd have to do something like this too: http://forums.hybridz.org/showthread.php?t=103007

Didn't get a chance to do anything to the car today, but I did run out and take a couple pictures and a measurement. That part of the frame that holds the bushings in came out at .108" on my caliper. It was kind of a weird angle to measure at but that should be accurate within a few thousandths. John, I took a couple pictures of the control arm for you. I cut the end of the arm off with my bandsaw. I just cut enough so that the welds that hold the large washers on were gone. Then I used some 5/8" threaded tube ends from Coleman Racing. These are made to fit a 1" ID tube, so they're too damn big for the control arms. Ron Tyler offered to turn them down for me (THANK YOU RON!) and so he turned them down to .745" with a 1" head that almost matches the tube on the control arm perfectly. This worked out pretty good. On one control arm they are just a little teeny bit loose, on the other one I had to spend about 30 minutes with a Dremel and a drum sander to get the inside hogged out enough to slide the tube ends in. I was a bit impatient and really had to hammer the end in on one side, that was pretty dumb because it took me about an hour to get it out later on... Anyway I drilled a couple holes in the control arm and plug welded the tube end in, then beveled the end and welded it there as well. I used a heat setting of 7 and a wire speed of 5, so I don't think there will be any lack of penetration on the welds, but I think welding on these tube ends is one of those places where a tig would come in handy.

Bandsaw is my most used tool for cutting. 2nd is probably the cutoff wheel. The cheap HF ones have a lifespan about 1/10th of a really good one, I can say that from personal experience. So I definitely agree with John on this part. Interestingly I did buy a replacement bandsaw blade from McMaster Carr thinking it would be better quality than the HF ones, and it went dull in about 1/4 the time of the HF blades. Some cheap blades must be better than others. The Hecho In Mexico HF blades seem to be good for the money anyway.

I'll post more detailed pics of the arms when they're all done John, don't worry. Not so. When you pull the bolt out the spacers stick out farther than the housing, so you can just pull the inside of the control arm straight down and it comes out. So two bolts, one in front and one in back and the inside of the control arm pulls straight down and out. I'm not too worried about that critical placement of the holders. The way I mocked it up the first time was just by clamping the front down tight and leaving the rear loose. I set the control arm the proper distance from front to rear (marked the center of the control arm) and then just tapped the rear housing with a hammer to make sure it was solidly hitting the control arm then tightened the bearing cap down. It seemed to work pretty good on the mockup trial. If all else fails, my version of the toe adjuster is "less than rigid" in that plane so it will fairly easily take up a couple thou slack and not really preload the bearings much at all. I was thinking about the frame rails more though Terry, and I'm starting to think I should do what bjhines did with his cage and a lot of drag racers do, and run diagonal bars from the cage down to the floor there. I already have the frame stitch welded to the floor, but maybe about 10 or so plug welds through to a plate that then connected into the cage might be in order...

No, I ran a prop valve and had it all the way biased towards the rear. Then I went the further step of removing it entirely so that it wasn't cutting ANY pressure to the rear, and I still couldn't get it exactly right. The next thing to do would have been dual master cylinders and put a smaller master on the back to increase the rear pressure. Never got that far though...

Just a clarification. The billet mustache bar is meant to be used with poly bushings. Yeah... I know... You'd have to make aluminum bushings to go into the mustache bar to solidly mount the diff.

I can back this up. I was running the non-vented Toy calipers with 280ZX rear disks having trouble dialing in the bias, no matter what I did I couldn't get enough rear bias for my liking. I ended up throwing the stock front calipers back on, and was able to really dial in the bias well, but that was when I punched a hole through the brake pad at the track. After that I went back to the 4x4 calipers and never really got that setup dialed in perfect before I decided to go with Wilwoods instead. So while I don't think the 4x4 calipers were the be all and end all, they did have larger pads and larger heavier calipers, so they could absorb more heat into them. They also do have a lot more stopping power than the stockers, as evidenced by my not being able to get the bias right even with NO proportioning valve in the system. The key to good braking isn't just clamping power, it's also bias. If you put 12" Wilwoods in the front and stock drums in the back, your braking distances (at least the first few times before fade sets in) will be LONGER with the Wilwoods because the rears will not be contributing at all in that case. Although the car continued to get faster, I never had another repeat of the hole in the pad incident while running the Toy calipers...

By ID I meant Inside Diameter. They changed the inside of the ring gear size in 76. Forget about mixing and matching a ring and pinion. They are a set and won't take kindly to that. Even if you had two identical diffs it would be a REALLY bad idea to swap ring gears from one to the other. But what you're talking about is finding a 10 tooth pinion from something, and matching it with a 39 tooth ring gear from something else. That's is an especially bad idea because the pitch on the teeth won't match. So even though it's a numerical 3.90, the teeth won't mesh together correctly at all.

A trick for you Ron if you do go down that road. I just remembered you have to make a clutch stack compressor out of a bolt and nut to put the gears back in the carrier too. Also, looked it up at ringpinion.com, and here's what I found: Trac-Lok (T/L) Built by Dana Spicer for use in Spicer rearends, AMC rearends, and 1998 & older 10.25" Ford rearends. The old design built up until about 1989 was weak. The 1990 and newer design is fairly strong and even rivals the Powr-Lok for impact durability, but the clutches do not provide as much lock-up force and tend to wear out in about 50,000 miles if used in the rear. Works better in the front of vehicles because it's not aggressive. The main selling points for this design are the fact that clutch chatter is almost non-existent, and it is very inexpensive. These two points make it a great unit for many applications and a very good value for the money. This unit makes a great front limited slip and works well for those who need a little extra traction but cannot tolerate clutch chatter. The Trac-Lok came factory installed in many models such as D28, D44, D60, AMC 20, AMC35, 10.25" Ford. The problem with this unit is that it is not very aggressive and power transfer is minimal. Also, 1988 and earlier units tend to break fairly easily. (1piece case, 2 pinion gears, and 2 tab clutches). (factory) Powr-Lok (P/L) This clutch type limited slip is the strongest and most aggressive limited slip differential available from Dana Spicer. It is a clutch type unit using floating cross shafts that ride up on ramps in the case. When power is applied, the shafts ride up the ramps and load the clutches for a positive engagement. A Powr-Lok will not lock up 100%, but it is a very durable unit that will hold up fairly well with tall tires. It can be rebuilt, and can be set up smooth or aggressive by changing the clutch design or stacking configuration. Powr-Loks are easily identified by their 2-piece case. They are a very strong unit due to the 4 spider gear design that provides twice as many teeth to carry the load as a 2 spider gear unit does. However, the case bolts can stretch or loosen after severe use over time. (4 pin, 4 tab clutches) (factory) Detroit Truetrac (TT) Based on the worm gear principal and works like clutch type positraction. Does not wear out, not recommended for tall tires over 33". Detroit Truetracs are similar in design to the Gleason Torsen®, only the Truetracs hold up well with reasonably tall tires. They use worm wheel gears that work on the same principle as a worm gear. When the unit is loaded, the worm wheels are forced away from each other and against the case. They develop locking torque by the light friction between the worm wheels and the case. This light friction is multiplied by the ratio of the worm wheel which depends on the size of the worm wheel relative to the size of the side gear. The manufacturer can change the amount of torque biasing or lockup by simply changing the diameter of the gears, or the pitch and spiral of the teeth. A larger difference in the size for the worm wheels and side gears (smaller worm wheels and larger side gears) will increase the lockup force. Increasing the pitch and spiral of the teeth will also increase the lockup forces. Like everything, there is a limit as to how much lockup force is reasonable. Making the unit too "aggressive" will cause tire scrub during everyday driving and will cause the unit to wear out too quickly. All of the feedback that I have received from customers indicates that the unit works very well for mud and snow, while going unnoticed during every day driving. When used in situations like rocky trails where one wheel gets off the ground, the unit will not lock up 100%. Light application of the brakes will help the differential engage more transferring power to the tire that is still on the ground. For extreme situations where the vehicle will have one wheel in the air often a locking differential provides better power transfer to the wheel on the ground. Detroit Truetracs are designed for medium duty 2WD and 4WD applications. They work well in the front and rear, and are so smooth that there is little or no hint of resistance in the steering wheel when used in front drive steering axles. Like the Gleason Torsen®, the Detroit Truetrac does not bang or clunk, has no clutch chatter, does not wear out like clutch type positractions, does not need limited slip additive, and needs no preload or clearance adjustments. Almost sounds too good to be true doesn't it? The only drawbacks to the Truetracs are their inability to provide lockup 100% like a locking differential can. Although Gleason no longer makes the Torsen® differential, the Detroit Truetrac is a proven design that is available for many popular applications. (aftermarket) 1 yr warranty

There are 2 D44 LSD's that I'm aware of. The Powr-Lok which is basically just like the Nissan LSD. Salisbury LSD, ramps, torque sensing, the whole 9 yards. Then there is the Trak Lok which is literally the crappiest clutch LSD you can buy, at least in my experience. I used to sell replacement LSDs all the time, and the parts were about as much as the whole thing, so we almost never tried to fix them. I seem to recall they usually ran about $140. The Trac Lok has belleville springs under the clutch stack, and that was the only thing providing pressure to the clutch stack. So you could shim it tighter, but the clutches were weak and that would be the next issue you'd run into. I seem to remember problems with the case too, like the cross pin shaft wallowing out the hole just like our R200 open diffs tend to do. It was the "trick question" diff when we were learning about LSDs, because it looked like an open carrier. Big holes on the sides to put the gears in. You could only tell it was LSD by looking at the ends and seeing the holes where the tabs for the clutches went. Dana makes their own version of a helical LSD called a TrueTrac. If they have one for the D36, it probably runs $300. I know they have it for the D30 and the D44, and the D30 version has an adjustable preload "block" that you can tighten to make the diff more aggressive as I recall (the hot ticket for Volvos). It's been 3 or 4 years, so things might have changed, or I might just remember wrong. Maybe people have figured out how to make them work without grenading. Maybe Dana has improved the design. All I know is I wouldn't put one in my car...

The saddles in the frame are thick, for the record. Probably .120. I think its the thickest metal I've seen on a Z, except maybe the TC bucket.

So what's the ETA on this sucker? And how many years in the making??? I think you've got me beat by a substantial margin. Mine is down at least 3 years now...

That looks pretty damn good! Keep it up!

You want to spell that out a little clearer for me? I'm not exactly following what you mean.

Wow, dude! Just... wow.

Ron, read this: http://forums.hybridz.org/showthread.php?t=106354 Keith gives reasons and alternative strut suggestions, Cary states the case for the AD. Plus a lot more...

Nothing is wrong with the good old 2 man bleeding system. All of this is a side track from the real issue.

Just reminded myself of why I can not just bolt these things in. The alignment of the bearing holders has to be (relatively) exact. So I guess I just need to figure out where part it is better to weld them to.

I'm starting to think that I could get away with not welding in the bearing holders at all, and just use the bushing clamps to secure the bearing holders. Or, I could weld the bearing holders to either the frame on top or the bearing holders and the crossmember on bottom. I'm still thinking welding to the frame is the better decision for strength, and that way if I did pull the diff I wouldn't have to disconnect the control arms. I'm off to dig in on the left side front bearing holder. if anyone has any advice on welding or not or which parts to weld to what, post away...

More progress. This is really starting to come together! I used a die grinder and hogged out the upper part of the bushing clamp in the rear. Then I cut the center out of the bottom, and hogged it out to fit the bearing holder. Then I hogged out the frame part on the top, and did likewise on the diff crossmember: Bolted everything up and checked to make sure it was all moving smoothly: All looked and felt good as it went through the suspension travel. Nothing left to do but check the strut and make sure it was moving straight. Heres the results from the driver's side. Not quite perfect when fully extended but the nut goes on really easily: Heres the toe adjuster. I painted this thing a few months back and due to all the modifications with the swaybar and now the control arms, it already needs new paint. I haven't even driven the car yet! oh well, just one more thing to do... Fully compressed (it just doesn't get any better than this!):